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Use of carbon fibers for repair of abdominal-wall defects in rats   总被引:3,自引:0,他引:3  
Carbon in the form of 8-micron fibers induces growth of connective tissue. The purpose of this study was to measure and histologically characterize tissue ingrowth occurring in carbon fibers implanted for up to 12 months in abdominal-wall defects in rats, compared with polypropylene mesh. Carbon fibers induced significantly more tissue ingrowth than polypropylene mesh at 6 to 12 months postoperatively. The predominant tissues associated with carbon fibers and polypropylene mesh were dense connective tissue and fat, respectively. Fragmentation of the implants did not occur, and implant debris was not found in the regional lymph nodes. Carbon fibers are potentially useful for reinforcing abdominal-wall defects.  相似文献   
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A 66-year-old woman presented with an alien limb syndrome without dementia. The course of her illness was unremitting and at autopsy 6 years later her diagnosis was confirmed as corticobasal degeneration without Alzheimer-type pathology. Although the presence of ballooned achromatic cortical neurons and cell loss from the substantia nigra distinguishes such patients, the site and density of achromatic neurons has not previously been quantified. We show that immunohistochemistry for the cell stress protein ubiquitin selectively stains these achromatic neurons, whereas they do not stain for abnormally phosphorylated tau protein. Phosphorylated neurofilament antibodies recognise both ballooned and non-ballooned neurons. In this case, high densities of ubiquitin-positive ballooned neurons were found in frontal cortical regions with the highest densities in layers V and VI of the anterior cingulate cortex. In addition, high densities of ubiquitin-positive ballooned neurons were found in the insular cortex, claustrum and amygdala. These results confirm past reports of frontal pathology, but show that there is also considerable pathology in insular and parahippocampal cortical regions and some subcortical regions. Our findings suggest that the distribution and staining characteristics of ballooned neurons in corticobasal degeneration may help to differentiate these cases pathologically, while the absence of dementia appears to be an important clinical criterion.  相似文献   
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This article identifies common characteristics of educationally related programs that form a common basis for understanding and working with gifted programs. Special approaches and programs for educational enrichment as well as specific activities that have been successful are discussed.  相似文献   
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Background: Patients who suffer with gastroesophageal reflux Disease (GERD) endure a worsening of symptoms as their weight increases. When medical treatment of this condition in the morbidly obese patients fails, surgical intervention may be indicated. Choosing a procedure which not only helps achieve weight control but which also relieves symptoms and complications of GERD is the goal. We present a review of patients who have undergone Roux-en-Y Gastric Bypass (RYGBP) and related procedures for this disease. Methods: One hundred eighty-eight patients undergoing surgery for morbid obesity and for GERD in 1992-1996 were contacted by mail or phone. All of these patients had undergone preoperative esophagogastroduodenoscopy to grade the severity of their disease. Their preoperative symptoms were compared to those experienced postoperatively. Results: One hundred thirty patients underwent a RYGBP with modified Hill fundopexy, 22 patients underwent a distal gastrectomy with modified Hill fundopexy, 8 patients underwent distal gastrectomy alone and 28 patients underwent RYGBP alone. There have been no deaths. There were nine surgical complications, eight early and one at 2.5 years postoperation. Follow-up is 4-48 months. The average BMI dropped from 43 to 30.2 kg/m2. Whereas all patients were on some form of medical therapy before surgery, only 14 reported the need for medication postoperatively. Conclusions: Surgical intervention for weight control and treatment of GERD has been highly successful in our experience both with respect to weight control and to the reduction of reflux symptoms. Depending upon endoscopic and operative findings a RYGBP with or without an antireflux procedure can provide dramatic improvement. Gastrectomy with antireflux modifications is appropriate in selected cases.  相似文献   
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In a survey of the 50 State health agencies in the spring of 1992, officials were asked about their manpower and research needs in the specific areas of administration, behavioral and social science, education and information, environmental health, environmental protection, epidemiology, laboratory, law, occupational health, policy and planning, and statistics. In all, 40 agencies (80 percent) responded. Indepth telephone interviews to determine whether universities and schools and graduate programs in public health filled these needs completed the data collection process. Agency officials indicated that their resources were least adequate in environmental protection, behavioral and social science, and occupational health. They did not feel their research needs were being met. There was a general feeling that universities and schools and programs in public health have different agendas than State agencies and that practical solutions to the shortage of research resources are not forthcoming from these sources. Suggestions are made as to what can be done to improve relationships between those who train public health personnel and those who employ them.  相似文献   
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Current immunosuppressive regimens for clinical transplantation are immunologically non-specific, are associated with acute and chronic toxic side-effects [1] and are unable to prevent chronic graft loss in a significant proportion of patients. Additionally, new and increasingly powerful drugs are being introduced to induce non-specific immunosuppression, and therefore this is likely to be followed by an increase in related complications such as the induction of cancers. Hence, there is a need for an alternative approach. It has been shown that long-term survival of murine cardiac grafts can be induced by the monoclonal antibody YIS 191 that depletes CD4 +T cells in vivo [2]. In this study, we have investigated the ability of a non-depleting antibody to produce better graft survival.  相似文献   
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